AFR 101

Caroobs

Joined: 03/14/12

Posts: 273

AFR 101
08/07/12 10:50 AM

Ok, so I've done a lot of reading at this point on AFR values and how they affect power and heat. I have the PCV and Autotuner installed, and I need to get this baby tuned. As far as I can tell:

lower AFR - 12.8 - richer - more power - less heat
higher afr - 14.1 - leaner - more gas mileage - more heat

I know that things get more complex, but is this basic starting point more or less correct?

I am looking overall for balanced street riding. I have my target AFR set high (14.1) at cruising speeds for gas mileage, and low (12.8) at higher RPMs for power when I want it. Living in south Louisiana heat is a big deal, so I want to know how that factors in as well. Once I get a good starting spot, I plan to rent some time on a dyno, just to get some actual numbers and fine tune things.

'09 Candy Green ZX-14, flies out, Yoshi slipons, Pipercross air filter, PAIR blocked, PC-V, Speedohealer, Illumiglo gauges, Throttlemeister cruise control, Monster shorty levers, Corbin seat, 35w HID lights.

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Danno

Location:

Southwestern Illinois

Joined: 12/18/11

Posts: 2142

RE: AFR 101
08/08/12 2:32 AM

Any IC engine runs best when it's just on the verge of lean piston melt. Running richer will not produce more power, but it's safer for the engine because of less heat. In any lower rpm range, some richness is required for acceleration, but on top, lean runs best. Just don't lean out to the point of meltdown. The stoichiometric (ideal) afr is around 14.6:1. This is the ratio at which all fuel and air are consumed during combustion. As you can see, it's pretty lean.

* Last updated by: Danno on 8/8/2012 @ 2:36 AM *

'07 CPB Blue; ZGST windscreen with MRA X-screen adjustable spoiler, tube bar adaptor, PC III, ATRE,BMC air filter, modified stock seat with 2nd Look cover,Scorpion Flame Ti slip-ons, Galfer rotors front and rear, braided-stainless lines, C-F 10R front fender, C-F hugger, C-F inner fairing panels, painted foreman's fins with faux C-F inlay, polished rim lips wired for heated gear and accessories, Givi V35 side bags and E41 topcase with SW-Motech qd mounts

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seno

Location: Lithia, Florida

Joined: 08/31/11

Posts: 592

RE: AFR 101
08/12/12 7:53 AM

These bikes seem to make the most power with AFR 12.8-13.2. If you want a custom map let me know, I have one for your bike (muzzy pipe & flies out), PM me email address and I'll send it.... 13.1 is what these bikes like on the dyno.

2015 30th Anniversary Edition 14R #250-> Brock's CT Ceramic Coated, Ivan's ECU Flash V2 & Map, Block off plates, HM Strain gauge quickshifter, GPR Damper, Spiegler lines, Muzzy's Sliders, Pazzo levers, Rizoma Next Fluid Tanks, DDM Ultra 5500K HID's Low & Hi, DB Windscreen, Cox Radiator guard, gold titanium bolts... too many to list at this point

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Caroobs

Joined: 03/14/12

Posts: 273

RE: AFR 101
08/12/12 4:34 PM

PM sent. Will be neat to get some numbers from a couple different maps.

'09 Candy Green ZX-14, flies out, Yoshi slipons, Pipercross air filter, PAIR blocked, PC-V, Speedohealer, Illumiglo gauges, Throttlemeister cruise control, Monster shorty levers, Corbin seat, 35w HID lights.

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